PDF Watermark
Free online pdf watermark that runs entirely in your browser.
How the PDF Watermark works
The PDF Watermark works on Choose file, Watermark text (e.g. CONFIDENTIAL), Opacity (%), Angle (degrees), Font size (pt), Pages (e.g. all or 1-3) and shows the result as you type. The same input always gives the same answer — refresh the page and you will see exactly the same figure, and nothing you type is sent anywhere.
Formula used
PDF Watermark is computed by the formula below, using the inputs you provide.
Inputs used: Choose file, Watermark text (e.g. CONFIDENTIAL), Opacity (%), Angle (degrees), Font size (pt), Pages (e.g. all or 1-3).
Worked example
Run the tool above with your own file — the result is a direct download, so there are no numbers to show here.
Frequently asked questions
- Is the PDF Watermark free?
- Yes. There is no signup, no usage limit and no watermark — the generator runs entirely in your browser.
- Does the PDF Watermark store or send my data?
- No. Every calculation happens locally in the page, so the numbers you type are never uploaded or logged.
- Does it work on a phone and offline?
- Yes — the page is a single lightweight file that adapts to any screen size. Once it has loaded it keeps working without a network connection.
- What inputs does the PDF Watermark need?
- Choose file, Watermark text (e.g. CONFIDENTIAL), Opacity (%), Angle (degrees), Font size (pt), Pages (e.g. all or 1-3). Change any of them and the result updates instantly.